Savannah was paid $87 for 12 hours of babysitting and $65.25 for 9 hours. What is the constant of proportionality that describes this relationship?
Responses
A 0.140.14
B 7.257.25
C 12.512.5
D 65
To find the constant of proportionality that describes this relationship, you have to divide the total amount Savannah was paid by the number of hours she worked for each job separately. This constant of proportionality is essentially the rate she is paid per hour (the unit rate).
First, let's find the rate for the 12-hour babysitting job:
\( \frac{$87}{12 \text{ hours}} = $7.25 \text{ per hour} \)
Then, let's find the rate for the 9-hour babysitting job:
\( \frac{$65.25}{9 \text{ hours}} = $7.25 \text{ per hour} \)
Since both rates are the same, the constant of proportionality, which is the hourly rate Savannah is paid for babysitting, is $7.25 per hour.
The correct answer is:
B 7.25